At least 43 civilians were killed in US-led airstrikes that targeted a residential building in Syria's Raqqa city, officials said on Saturday.The airstrikes on Friday targeted the al-Jamili building in Raqqa and most of those killed were women and children, SANA news agency reported.Civilian casualties have increased recently as a result of the intensification of US airstrikes on Raqqa, the de facto capital of the Islamic State (IS) terrorist group, and other IS strongholds in northern and eastern Syria.A day earlier, 20 civilians were killed when a US-led airstrike targeted residential buildings in Raqqa, including a hospital and a hotel.Last Sunday, 20 civilians were killed in similar airstrikes in Raqqa.Last Thursday, 35 civilians were killed by airstrikes on the IS-held city of Mayadeen in the eastern province of Deir al-Zour.The Syrian government has repeatedly denounced the attacks targeting civilians, branding the operation of the US-led anti-terror coalition in Syria as "illegitimate".